AD 2004-15-09

This amendment adopts a new airworthiness directive (AD), applicable to certain Bombardier Model DHC-8-101, -102, -103, -106, - 201, -202, -301, -311, and -315 airplanes. This amendment requires an inspection of the fuel tube assembly of the auxiliary power unit (APU) for clearance from adjacent components; and an inspection of the fuel tube assembly and the bleed air duct shroud for discrepancies (insufficient clearance, nicks, dents, chafing, or other damage); and related investigative and corrective actions if necessary. This amendment also requires relocation of certain support clamps on the APU fuel tube assembly. This action is necessary to prevent a fuel leak caused by chafing of the APU fuel tube assembly, which could result in fire in the center wing area. This action is intended to address the identified unsafe condition.

Final rule.

2004-15-09 Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 39-13743. Docket 2003-NM-285-AD.

Applicability: Model DHC-8-101, -102, -103, -106, -201, -202, - 301, -311, and -315 airplanes, serial number 003 through 585 inclusive; certificated in any category; with auxiliary power unit (APU) installation per Standard Option Only (S.O.O.) 8155 or Change Request (CR) 849SO08155.

Compliance: Required as indicated, unless accomplished previously.

To prevent a fuel leak caused by chafing of the APU fuel tube assembly, which could result in fire in the center wing area, accomplish the following:

Inspection, Relocation and Related Investigative and Corrective Actions

(a) Within 6 months after the effective date of this AD: Do a general visual inspection of the APU fuel tube assembly for discrepancies. The inspection includes examining the routing of the fuel tube assembly to ensure that the tube has sufficient clearance between the shroud of the bleed air ductand the gust lock cable; and inspecting the fuel tube assembly and the bleed air duct shroud for other discrepancies such as nicks, dents, chafing, or other damage. If the inspection shows no discrepancies, before further flight, relocate the clamps on the fuel tube assembly. If the inspection shows discrepancies, before further flight, do the applicable related investigative and corrective actions, and relocate the clamps on the fuel tube assembly. Accomplish all actions per the Accomplishment Instructions of Bombardier Service Bulletin 8-49-19, Revision A, dated July 7, 2003.

Note 1: For the purposes of this AD, a general visual inspection is defined as: "A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked."

Inspections Accomplished Per Previous Issue of Service Bulletin

(b) Actions accomplished before the effective date of this AD per Bombardier Service Bulletin 8-49-19, dated May 13, 2003, are considered acceptable for compliance with the corresponding action specified in this AD.

Alternative Methods of Compliance

(c) In accordance with 14 CFR 39.19, the Manager, New York Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance for this AD.

Incorporation by Reference

(d) Unless otherwise specified in this AD, the actions shall be done in accordance with Bombardier Service Bulletin 8-49-19, Revision A, dated July 7, 2003. This incorporation byreference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, suite 410, Westbury, New York; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .

Note 2: The subject of this AD is addressed in Canadian airworthiness directive CF-2003-22, dated September 3, 2003.

Effective Date

(e) This amendment becomes effective on August 31, 2004.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Bombardier Model DHC-8- 101, -102, -103, -106, -201, -202, -301, -311, and -315 airplanes was published in the Federal Register on May 19, 2004 (69 FR 28863). That action proposed to require an inspection of the fuel tube assembly of the auxiliary power unit (APU) for clearance from adjacent components; an inspection of the fuel tube assembly and the bleed air duct shroud for discrepancies (insufficient clearance, nicks, dents, chafing, or other damage); and related investigative and corrective actions if necessary. That action also proposed to require relocation of certain support clamps on the APU fuel tube assembly.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public.

Conclusion

The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact

The FAA estimates that 125 airplanes of U.S. registry will be affected by this AD, that it will take approximately 1 work hour per airplane to accomplish the required actions, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $8,125, or $65 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations adopted herein will not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained inthe Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

39.13 [Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive: